PSSA MATH GLOSSARY


Mathematics Assessment Anchor Glossary
Grade 6
Chord: A line segment whose endpoints are on a circle.
Circumference: The distance around a circle.

Composite number: A whole number having more than two factors.
Diameter: A line segment that has endpoints on a circle and passes through the center of the
circle.
Expanded notation: A way to write numbers that shows the value of each digit
(e.g., 4372 = 4000+300+70+2).
Greatest common factor (GCF): The largest factor that 2 or more numbers have in common.
Heptagon: A polygon with 7 sides.
Histogram: A bar graph in which the labels for the bars are numerical intervals.
Hypotenuse: The longest side of a right triangle (which is also the side opposite the right angle).
Least common denominator (LCD): The least common multiple of the denominators in two or

more fractions.
Least common multiple (LCM): The smallest number, other than zero, that is a common
multiple of two or more numbers.
Leg (of a right triangle): Either of the two sides that form the right angle in a right triangle.
Line plot: A graph showing the frequency of data on a number line.
Nonagon: A polygon with 9 sides.
Plane: A flat surface that extends infinitely in all directions.

Prime number: A whole number that has exactly two factors, 1 and itself.
Quadrants: The four regions of a coordinate plane that are separated by the axes.
Radius: A line segment that has one endpoint on a circle and the other endpoint at the center of

the circle.
Range: The difference between the greatest and least numbers in a set of data.
Rate: A ratio that compares two quantities having different units (e.g., 95 miles in 2 hours).

Ratio: A comparison of two numbers using division.
Regular polygon: A polygon that has all sides congruent and all angles congruent.
Repeating decimal: A decimal that has a repeating sequence of numbers after the decimal

point.
Similar polygons: Polygons that have the same shape, but not necessarily the same size.
Corresponding sides of similar polygons are proportional.

Straight angle: An angle with a measure of 180º.
Terminating decimal: A decimal that contains a finite number of digits.
Transformation: The moving of a figure by a translation (slide), rotation (turn) or reflection (flip).
Unit price: The price of a single item or amount (e.g., $3.50 per pound).
Unit rate: A rate with the second term being one unit (e.g., 50 mi/gal, 4.5 km/sec).
Venn diagram: A diagram that shows relationships among sets of objects.

Whole number: Any of the numbers 0, 1, 2, 3, 4, 5, … (and so on).

X-axis: The horizontal number line on a coordinate plane.
Y-axis: The vertical number line on a coordinate plane.